Cos(pi/2 - x) = sin(x). sec(x) = 1/cos(x), so the left side would be sinx/cosx = tanx. So it checks out.
It is most likely to combine music and poetry
Ballads are generally a verse or a poem which is set to a specific music.
The idea is to develop a narrative and enhance the experience of story telling.
Ballads are characteristics of the old medieval English story-telling culture from it developed into a complete art form by the 19th century.
Ballads are still popular among both the young and old as fine forms of entertainment and art
He was facing the burning bush, and god spoke to him.
